Video-calling app developer Tango announced today that it has raised $42 million in its second round of funding.

The Tango app lets tablet and smartphone users make video calls to other Tango users, much like Apple’s FaceTime app for the iPhone 4. The service works over 3G and 4G networks.

The company also announced that it is releasing a desktop version of the application. That will let individuals start video calls between multiple devices like the iPhone, a computer, an Android phone or an iPod Touch. It will work with any device running Android, Windows or the iPhone iOS operating system that has a camera. The service will also be free, the company said today.

An application for Mac users isn’t available yet, but it will probably come as the company rolls its software out to more platforms, said Eric Setton, chief technology officer of Tango.

AI Weekly

The must-read newsletter for AI and Big Data industry written by Khari Johnson, Kyle Wiggers, and Seth Colaner.

Included with VentureBeat Insider and VentureBeat VIP memberships.

Draper Fisher Jurveston led the funding round.

Tango plans to use most of the funds to ramp up its team in China. It opened an office in Beijing recently and plans to use that office to recruit more engineering talent, Setton told VentureBeat.

“Of all the great centers of engineering, Beijing and Silicon Valley stand out — particularly in our space,” he said. “And a lot of our team in the U.S. speaks Mandarin, so we have some strong ties over there.”

The service relies on peer-to-peer networking that most file-sharing applications rely on today. That means the technology doesn’t rely entirely on servers and can scale up quickly — as it already has, because the app turned out to be pretty popular. Smartphone and tablet users downloaded it around 1 million times in its first 10 days after release.

“The video and the audio, they go straight from the computer or phone to the people you’re speaking to,” Setton said. “That way there’s the shortest delay on the network, and great for us because we don’t need to scale that cost.”

Tango has 18 million members in 190 countries. The Palo Alto, Calif.-based company raised $5 million in funding from individual investors including Bill Hambrecht, Michael Birch, Bill Tai, and Daniel Scheinman in its first round of funding. The company has raised $47 million in funding to date. The company was founded in September 2009.

VentureBeat's mission is to be a digital town square for technical decision-makers to gain knowledge about transformative enterprise technology and transact. Learn More